Enhanced Bone Formation by Rapidly Formed Bony Wall over the Bone Defect Using Dual Growth Factors

BACKGROUND@#In guided bone regeneration (GBR), there are various problems that occur in the bone defect after the wound healing period. This study aimed to investigate the enhancement of the osteogenic ability of the dual scaffold complex and identify the appropriate concentration of growth factors (GF) for new bone formation based on the novel GBR concept that is applying rapid bone forming GFs to the membrane outside of the bone defect. @*METHODS@#Four bone defects with a diameter of 8 mm were formed in the calvaria of New Zealand white rabbits each to perform GBR. Collagen membrane and biphasic calcium phosphate (BCP) were applied to the bone defects with the four different concetration of BMP-2 or FGF-2. After 2, 4, and 8 weeks of healing, histological, histomorphometric, and immunohistochemical analyses were conducted. @*RESULTS@#In the histological analysis, continuous forms of new bones were observed in the upper part of bone defect in the experimental groups, whereas no continuous forms were observed in the control group. In the histomorphometry, The group to which BMP-2 0.5 mg/ml and FGF-2 1.0 mg/ml was applied showed statistically significantly higher new bone formation. Also, the new bone formation according to the healing period was statistically significantly higher at 8 weeks than at 2, 4 weeks. @*CONCLUSION@#The novel GBR method in which BMP-2, newly proposed in this study, is applied to the membrane is effective for bone regeneration. In addition, the dual scaffold complex is quantitatively and qualitatively advantageous for bone regeneration and bone maintenance over time.

Current Opinion in Molecular Pathology of Ameloblastoma: A Literature Review

Ameloblastoma is the most representative epithelial odontogenic tumor in the craniofacial region. Through several studies on Ameloblastoma that have been conducted so far, we have been able to get closer to the reality of Ameloblastoma. However, groundbreaking insight into the pathophysiology of Ameloblastoma has not yet been provided.This review assessed three aspects of five recently published papers on Ameloblastoma: cancer stem cells, calcium signaling, and tumor microenvironment, and compared them with previous studies on tumor physiology, including cancer. In addition, the characteristics of Ameloblastoma revealed by the experimental methods presented in the currently published five papers provide the possibility of Ameloblastoma as a study model in general tumor or cancer studies. Furthermore, the mechanisms of action of the chemicals identified in the studies support their potential as candidates for the second-line treatment of Ameloblastoma.

Reliability and validity of the Korean version of organizational justice questionnaire

BACKGROUND: Many studies show that organizational justice (OJ) is related to psychological determinants of employee health. To prevent health problems related to OJ in Korean workplaces and to accurately measure OJ, we developed the Korean version of the Organizational Justice Questionnaire (K-OJQ) and assessed its validity and reliability. METHODS: A questionnaire draft of the K-OJQ was developed using back-translation methods, which was preliminary tested by 32 employees in Korea. Feedback was received and the K-OJQ was finalized. This study used data from 303 workers (172 males, 131 females) in Korea using the K-OJQ, job stress, and lifestyle questionnaires. RESULTS: Cronbach’s α coefficients of the internal consistency reliability was 0.92 for procedural justice and 0.94 for interactional justice. Factor analyses using SPSS 24 and Amos 23 extracted two expected factors, named procedural justice (7 items; range, 1.0–5.0) and interactional justice (6 items; range, 1.0–5.0) and showed a reliable fit (χ2 = 182; p = .000; GFI = .912; AGFI = .877; CFI = .965; RMSEA = .077). Furthermore, higher procedural justice and interactional justice levels were correlated with lower job demand (− 0.33; − 0.36), insufficient job control (− 0.36; − 0.41), interpersonal conflict (− 0.45; − 0.51), job insecurity (− 0.33; − 0.34), organizational system (− 0.64; − 0.64), and lack of reward (− 0.55; − 0.63). CONCLUSIONS: The K-OJQ was objectively validated through statistical methods. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s40557-018-0238-8) contains supplementary material, which is available to authorized users.

Analysis of Risk Factors and Management of Cerebrospinal Fluid Morbidity in the Treatment of Spinal Dysraphism

OBJECTIVE: Spinal dysraphism defects span wide spectrum. Wound dehiscence is a common postoperative complication, and is a challenge in the current management of cerebrospinal fluid (CSF) leaks and wound healing. The purpose of this study is to evaluate the risks of CSF-related morbidity in the surgical treatment of spinal dysraphism. METHODS: Ten patients with spinal dysraphism were included in this retrospective study. The median age of the cohort was 4.8 months. To assess the risk of CSF morbidity, we measured the skin lesion area and the percentage of the skin lesion area relative to the back surface for each patient. We then analyzed the relationship between morbidity and the measured skin lesion area or related factors. RESULTS: The overall median skin lesion area was 36.2 cm2 (n=10). The percentage of the skin lesion area relative to the back surface ranged from 0.6% to 18.1%. During surgical reconstruction, 4 patients required subsequent operations to repair CSF morbidity. The comparison of the mean area of skin lesions between the CSF morbidity group and the non-CSF morbidity group was statistically significant (average volume skin lesion of 64.4+/-32.5 cm2 versus 27.7+/-27.8 cm2, p<0.05). CSF morbidity tended to occur either when the skin lesion area was up to 44.2 cm2 or there was preexisting fibrosis before revision with an accompanying broad-based dural defect. CONCLUSION: Measuring the lesion area, including the skin, dura, and related surgical parameters, offers useful information for predicting wound challenges and selecting appropriate reconstructive surgery methods.

An Association Between the Prolonged Heart Rate-corrected QT Interval and Global Functional Outcome in Patients with Subarachnoid Hemorrhage

PURPOSE: Autonomic dysfunctions after subarachnoid hemorrhage (SAH) may lead to various arrhythmias, electrocardiographic abnormalities, and myocardial dysfunction. Prolongation of the heart rate-corrected QT (QTc) interval is frequently observed in patients with SAH. The aim of this study was to examine the associations between the QTc interval and global functional outcome in patients with SAH. METHODS: We studied 413 adult patients admitted via the emergency department within 48 hours after the onset of spontaneous SAH from January 2007 to December 2011. Among 413 patients with SAH, there were 154 male and 258 female patients whose mean age was 58.8+/-12.4 years. QT intervals were measured by standard 12-lead electrocardiography (ECG) and corrected by Bazett formulae. The QTc interval were considered prolonged at >450 ms in men and >470 ms in women. Outcomes were assessed using the length of hospital stay and the Modified Rankin scale (MRS) at discharge. RESULTS: One or more repolarization abnormalities occurred in 61.9% of patients. The most frequently observed ECG abnormality was QTc prolongation (54.9%), followed by non-specific ST-T changes(16.2%), ST-depression(9.2%), T-wave inversion(11.4%), U-wave(2.7%), and ST-segment elevation(1.7%). No correlations were found between age, sex, body mass index (BMI), location of aneurysm, and QTc interval. Multiple logistic regression analysis showed a relationship between prolonged QTc and Hunt Hess grades (p=0.012) in men, length of hospital stay (p=0.038) in women, Fisher grade (p=0.001), and MRS (p=0.006, p=0.011) in both. CONCLUSION: The prolonged QTc interval is more frequently observed in patients with severe hemorrhage and an unfavorable functional outcome (MRS 4-6) in SAH patients.

Intraventricular Atypical Meningiomas

A rare case of intraventricular meningioma that arose in the atrium of the left lateral ventricle was identified in a 51-year-old woman. Gross total removal was performed by transcortical approach. Histopathological findings showed meningothelial meningioma with a focal atypical area which had 8% of Ki-67 labeling index (LI). A large recurrence extending into the ipsilateral quadrigeminal cistern and opposite medial occipital lobe developed approximately 41 months after the first operation. The specimens obtained from the second resection showed atypical meningioma with 20% of Ki-67 LI but there were no anaplastic area. The patient underwent fractionated stereotactic radiotherapy. However, multiple local distant metastases were found in the occipital and cerebellar cortex suggesting cerebrospinal fluid dissemination apparently 24 months after the second operation. This report presents chronological progression of a rare intraventricular atypical meningioma with more aggressive transformation.

3-Dimensional Verification Technique for Target Point Error / 의학물리

For overall system test, hidden-target test have been used using film which leads to inherent analysis error. The purpose of our study is to quantify this error and to propose gel dosimeter based verification technique for 3-dimensional target point error. The phantom was made for simulation of human head and this has ability to equip 10 gel-dosimeter. BANGkit(TM) which we are able to manufacture whenever it is needed as well as to easily change the container with different shapes was used as a gel dosimeter. The 10 targets were divided into two groups based on shapes of areas with a planned 50% isodose line. All treatment and analysis was performed three times using Novalis and BrainSCAN(TM). The target point error is 0.77+/-0.15 mm for 10 targets and directional target point error in each direction is 0.54+/-0.23 mm, 0.37+/-0.08 mm, 0.33+/-0.10 mm in AP (anterior-posterior), LAT (lateral), and VERT (vertical) direction, respectively. The result of less than 1 mm shows that the treatment was performed through each precise step in treatment procedure. In conclusion, the 3-dimensional target point verification technique can be one of the techniques for overall system test.

The Dosimetric Effect on Real PTV and OARs at Various Image Fusion Protocol for Pituitary Adenomas / 의학물리

The purpose of this study is to verify the dosimetric effect on real PTV (planning target volume) coverage and safety of OARs (organs at risk) at various image fusion protocol-based radiosurgery plan for pituitary adenomas. Real PTV coverage and its variation was acquired and maximum dose and the volume absorbing above threshold dose were also measured for verifying the safety of optic pathway and brainstem. The protocol that can reduce superior-inferior uncertainty by using both axial and coronal MR (magnetic resonance) image sets shows relatively lower values than that of case using only axial image sets. As a result, the image fusion protocol with both axial and coronal image sets can be beneficial to generate OAR-weighted radiosurgery plan.

Development of Novalis Quality Assurance Protocol for Radiosurgery / 의학물리

In Republic of Korea, there are many Quality Assurance protocol for general radiation treatment machine such as linac. However, Quality Assurance protocol for radiosurgery treatment system is not ready perfectly. One of the radiation treatment machine for radiosurgery, novalis system needs to suitable Quality Assurance protocol for using it right way during radiation treatment and maintaining suitable accuracy for daily, weekly, monthly and annually periods. Therefore, in this article, we develop Quality Assurance protocol for novalis system. We collected and analysed domestic and foreign novalis Quality Assurance protocol. After that, we selected essential QA items and each tolerance range for developing proper QA protocol, and we made anatomical phantom for execution of selected QA items and evaluation of overall state of QA, and then, we use this measured value as a reference. Quality Assurance items are consisted of Mechanical accuracy QA part and Radiation delivery QA part. Mechanical accuracy QA part is comprised of radiation generation machine part, assistive devices part and multi-leaf collimator part. Radiation delivery QA part is divided into radiation isocenter accuracy and dosimetric evaluation. After that, developed novalis QA tables are made by using these QA items. These novalis QA tables would be used to good standard in order to maintain apt accuracy for radiosurgery in daily, weekly, monthly and annually periods.

Estimation of Inhomogeneity Correction Factor in Small Field Dosimetry / 의학물리

In this study, we estimated inhomogeneity correction factor in small field. And, we evaluated accuracy of treatment planning and measurement data which applied inhomogeneity correction factor or not. We developed the Inhomogeneity Correction Phantom (ICP) for insertion of inhomogeneity materials. The inhomogeneity materials were 12 types in each different electron density. This phantom is able to adapt the EBT film and 0.125 cc ion chamber for measurement of dose distribution and point dose. We evaluated comparison of planning and measurement data using ICP. When we applied to inhomogeneity correction factor or not, the average difference was 1.63% and 10.05% in each plan and film measurement data. And, the average difference of dose distribution was 10.09% in each measurement film. And the average difference of point dose was 0.43% and 2.09% in each plan and measurement data. In conclusion, if we did not apply the inhomogeneity correction factor in small field, it shows more great difference in measurement data. The planning system using this study shows good result for correction of inhomogeneity materials. In radiosurgery using small field, we should be correct the inhomogeneity correction factor, more exactly.

Estimation of CyberKnife Respiratory Tracking System Using Moving Phantom / 의학물리

In this study, we evaluated accuracy and usefulness of CyberKnife Respiratory Tracking System (SynchronyTM, Accuray, USA) about a moving during stereotactic radiosurgery. For this study, we used moving phantom that can move the target. We also used Respiratory Tracking System called Synchrony of the Cyberknife in order to track the moving target. For treatment planning of the moving target, we obtained an image using 4D-CT. To measure dose distribution and point dose at the moving target, ion chamber (0.62 cc) and gafchromic EBT film were used. We compared dose distribution (80% isodose line of prescription dose) of static target to that of moving target in order to evaluate the accuracy of Respiratory Tracking System. We also measured the point dose at the target. The mean difference of synchronization for TLS (target localization system) and Synchrony were 11.5+/-3.09 mm for desynchronization and 0.14+/-0.08 mm for synchronization. The mean difference between static target plan and moving target plan using 4D CT images was 0.18+/-0.06 mm. And, the accuracy of Respiratory Tracking System was less 1 mm. Estimation of usefulness in Respiratory Tracking System was 17.39+/-0.14 mm for inactivity and 1.37+/-0.11 mm for activity. The mean difference of absolute dose was 0.68+/-0.38% in static target and 1.31+/-0.81% in moving target. As a conclusion, when we treat about the moving target, we consider that it is important to use 4D-CT and the Respiratory Tracking System. In this study, we confirmed the accuracy and usefulness of Respiratory Tracking System in the Cyberknife.

Comparision of Anterior Segment Parameters in Angle-Closure Glaucoma Using Scheimpflug Camera

PURPOSE: To compare anterior segment parameters in angle-closure glaucoma (ACG), primary open angle glaucoma (POAG), and normal subjects (N) using a Schiempflug camera. METHODS: Central corneal thickness (CCT), lens thickness (LT), axial length (AL), anterior chamber angle (ACA), anterior chamber depth (ACD), and anterior chamber volume (ACV) were measured in ACG (93 eyes of 92 patients), POAG (90 eyes of 87 patients), and normal (91 eyes of 88 subjects) with Pentacam(R) and A-scan. All of the results and measurements were then compared. RESULTS: Compared to normal and POAG patients, ACG patients presented with significantly different measurements of CCT, LT, AL, and ACA, ACD, and ACV (p<0.05). Further, correlations were high between three measurements (ACA, ACD, ACV) in ACG, and the best correlations were found in acute angle-closure glaucoma (P<0.05). CONCLUSIONS: By using a Schiempflug camera it was possible to assess the correlation between anterior segment parameters (ACA, ACD, ACV) in glaucoma patients. The best correlations were found in acute angle-closure glaucoma, and thus anterior segment parameters can offer reciprocally complementary information.

Three Cases of Corneal Tattooing for the Treatment of Traumatic Iris Defect

PURPOSE: To investigate the effects of corneal tattooing on patients with a traumatic iris defect. CASE SUMMARY: Corneal tattooing operation was performed on three patients (3 cases) with a traumatic iris defect. In case 1, the cornea was dyed with Davidson(R) marking dyes (Bradley Products Inc., MN, US) and the amniotic membrane with the central incision was permanently transplanted. In case 2, both corneal dyeing and permanent amniotic membrane transplantation were performed on the area of partial iris loss. In case 3, corneal dyeing was performed after the intrastromal cornea was dissected. Corneal reepithelization was found in the first 2 cases 12 and 9 days after amniotic membrane transplantation, respectively. Three months after the transplantation, all three cases showed an improvement in best corrected visual acuity (BCVA), with an increase of one or more lines on the Snellen Chart. Simultaneously, preoperative monocular contrast and glare were also found to beimproved in all three cases. In both cases 1 and 2, 60% of the initially used dyes still remained in the cornea 6 months after the surgery, and in case 3, 90% of the initial dye remained. Except for the moderate astigmatism found earlier after the surgery in case 3, no serious complications developed. CONCLUSIONS: Corneal tattooing can improve the visual acuity and reduce glare in eyes with a traumatic iris defect and is cosmetically pleasing. Furthermore, corneal tattooing can be performed more easily and repeatedly than black diaphragm intraocular lens implantation.

Clinical Analysis of Novalis Stereotactic Radiosurgery for Brain Metastases

OBJECTIVE: The authors analyzed the effectiveness and therapeutic response of Novalis shaped beam radiosurgery for metastatic brain tumors, and the prognostic factors which influenced the outcome. METHODS: We performed a retrospective analysis of 106 patients who underwent 159 treatments for 640 metastatic brain lesions between January 2000 and April 2008. The pathologies of the primary tumor were mainly lung (45.3%), breast (18.2%) and GI tract (13.2%). We classified the patients using Radiation Therapy Oncology Group Recursive Partitioning Analysis (RPA) and then analyzed the survival and prognostic factors according to the Kaplan Meier method and univariate analysis. RESULTS: The overall median actuarial survival rate was 7.3 months from the time of first radiosurgery treatment while 1 and 2 year actuarial survival estimates were 31% and 14.4%, respectively. Median actuarial survival rates for RPA classes I, II, and III were 31.3 months, 7.5 months and 1.7 months, respectively. Patients' life spans, higher Karnofsky performance scores and age correlated closely with RPA classes. However, sex and the number of lesions were not found to be significantly associated with length of survival. CONCLUSION: This result suggests that Novalis radiosurgery can be a good treatment option for treatment of the patients with brain metastases.

Radiosurgery for Spinal Lesions

Spinal Stereotactic Radiosurgery (SRS) has become an important treatment modality for a broad range of spinal tumors and spinal vascular lesions. Recent clinical acceptance and awareness of the usefulness of spinal radiosurgery has escalated with the development of modern radiosurgical technology. Image-guided navigation systems incorporating non-invasive fiducial tracking and virtual simulation planning systems have made spinal radiosurgery increasingly effective and expanded the range of clinical applications for which it can be effectively used. Additional improvements such as Intensity Modulation and Micro-Multileaf Collimation that allow the accurate modulating and shaping of the radiation beam have also contributed greatly to the ability of clinicians to treat irregular and critically located lesions with greatly reduced collateral risk. Spinal Radiosurgery for spinal tumors can achieve similar clinical results to cranial stereotactic radiosurgery for brain tumors in terms of achieving local tumor control and improving quality of life and survival rates. Stereotactic radiosurgery, which has long been used for the treatment of intracranial lesions, is now recognized to be a viable option for treating spinal tumors and spinal vascular lesions.

Power Vector and Aberrations Using Corneal Topographer and Wavefront Aberrometer Before and After Pterygium Surgery

PURPOSE: To determine the power vector and aberrations before and after surgery for pterygium using a corneal topographer and a wavefront aberrometer. METHODS: The study group consisted of 34 eyes of 31 patients with pterygium, and were divided into two groups by pterygium size ( or = 3 mm, group II). Power vector and wavefront aberrations were evaluated using a corneal topographer (Oculus inc., Germany) and a wavefront aberrometer (LADARWAVE(R), Hartmann shack aberrometer, Alcon inc., US) at pre- and postoperative 1 week, 1 month, and 3 months. RESULTS: The preoperative blurring strength (B) and high order aberrations significantly decreased at postoperative 3 months in all groups (P or = 3 mm). To reduce aberrations and astigmatism effectively, we suggested surgical intervention in eyes with pterygia sized < 3.0 mm.

Long-term Outcome of Limbal Epithelial Cells Cultivated in Vivo on Amniotic Membrane Transplantation

PURPOSE: To investigate the characteristics and the results of long-term follow-up of limbal epithelial cells cultivated in vivo on amniotic membranes (LIVAM) in corneal limbal deficiency. METHODS: Twenty-two eyes of twenty-two patients diagnosed with corneal limbal deficiency underwent transplantation of in vivo cultivated corneal limbal epithelial cells on the amniotic membrane. Biopsy and immunohistochemical staining (AE5, MUC5AC) of the amniotic membrane cultivated for one week were performed to verify that the cultivated epithelial cells on the amniotic membrane were corneal epithelial cells. Impression cytology was performed to evaluate the characteristics of the transplanted corneal limbal epithelial cells at postoperative 1 week, 3 months, 6 months, and 1 year. RESULTS: Successful epithelial growth was observed on the amniotic membrane at one week. The epithelial cells were confirmed to be corneal epithelial cells by immunohistochemical staining. Transplanted in vivo cultivated corneal epithelial cells were confirmed to have corneal specificity by impression cytology and immunohistochemical staining at postoperative 1 week, 3 months, 6 months, and 1 year. CONCLUSIONS: In vivo cultured corneal epithelial cells showed morphological and immunohistochemical findings similar to those of normal corneal epithelial cells. Transplanted in vivo cultivated corneal epithelial cells were maintained and showed the characteristics of corneal epithelial cells. Transplantation of in vivo cultivated corneal limbal epithelial cells can be performed to reconstruct the corneal limbus in treating corneal limbal deficiency.

Novalis Radiosurgery of Primary Central Nervous System Lymphoma in Elderly Patients: Preliminary Results

OBJECTIVE: Primary central nervous system lymphoma(PCNSL) is a non-Hodgkin's lymphoma arising in the central nervous system. Combined chemotherapy and radiation therapy is the standard treatment for PCNSL. However, treatment induced neurotoxicity is a major problem especially in elderly patients. METHODS: From May 2001 to April 2004, elderly five patients with PCNSL confirmed via pathological examination were underwent Novalis radiosurgery in authors' institution, who were investigated retrospectively. Of these patients, 2 were male and 3 were female, with a mean age 68 years old (range 65~73). The number of lesions was 1 in 2 patients, 2 in 2, and 3 in 1. The mean follow up period was 12.6 months (range 8~16). RESULTS: Clinical symptoms and signs in all patients markedly improved within 1 weeks after Novalis radiosurgery. The Karnofsky performance status score was also improved from a pre-radiosurgery average of 68 to a post-radiosurgery one of 82. All of treated lesions showed a partial or complete regression of the original mass. There have been no complication following Novalis radiosurgery. CONCLUSION: The preliminary results of our experience indicate that radiosurgery with Novalis provides a safe and effective therapeutic alternative treatment of PCNSL in elderly patients.

Magnetic Resonance Spectroscopy of Patients with Acute Cerebral Infarction / 대한뇌혈관외과학회지

OBJECTIVE: MR spectroscopy is a noninvasive method of monitoring in vivo metabolite concentration changes over time. In this study we evaluated the usefulness of combined magnetic resonance imaging and spectroscopy on the diagnosis of cerebral infarction. METHODS: Combined magnetic resonance imaging and spectroscopy investigations were carried out with 1.5-T system in 18 volunteers, 10 patients with acute infarction (< 8 hours). RESULTS: Acute ischemic infarctions were characterized by decreased N-acetyl aspartate and elevation of lactate. CONCLUSION: Metabolic alterations in ischemic tissue can be monitored.

Fractionated Stereotactic Radiotherapy in Pediatric Diffuse Intrinsic Brain Stem Gliomas

OBJECTIVE: We treated 10 pediatric diffuse intrinsic brain stem glioma(BSG) patients with Novalis system (linac based radiotherapy unit, Germany) and examined the efficacy of the Fractionated Stereotactic Radiotherapy(FSRT). METHODS: A retrospective review was conducted on 10 pediatric diffuse intrinsic BSG patients who were treated with FSRT between May, 2001 and August, 2004. The mean age of the patient group was 7.7 years old. Male to female ratio was 4 to 1. The mean dose of FSRT was 38.7Gy, mean fractionated dose was 2.6Gy, mean fractionation size was 16.6, and target volume was 42.78cm3. The mean follow up period was 14 months. RESULTS: Four weeks after completion of FSRT, improvements on neurological status and Karnofsky performance scale(KPS) score were recorded in 9/10 (90%) patients and magnetic resonance imaging(MRI) showed decrease in target tumor volume in 8 pediatric patients. The median survival period was 13.5 months after FSRT and treatment toxicity was mild. CONCLUSION: It is difficult for surgeons to choose surgical treatment for diffuse intrinsic BSG due to its dangerous anatomical structures. FSRT made it possible to control the tumor volume to improve neurological symptoms with minimal complications. We expect that FSRT is a feasible treatment modality for pediatric diffuse intrinsic BSG with tolerable toxicities.